Stocking Options for 20g

Is this a 20 long or tall?

If long, cherry barbs or harlequin rasboras would be nice. Add in some platies maybe and corys for the bottom.
His grandpa is probably gonna go for some kind of smll predatory catfish likea Bumblebee, so any reccommendations should be too big to swallow. I'd also say his bottom if fully stocked there, too.
 
At only 3", none of those fish would be in danger except maybe platy fry. Just scratch the corys then.
I've heard of them going after neons in the night, but I agree he should probably be safe. Just saying he should be alert.
 
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